TUCKER, Ga. — The poultry industry is redefining how food safety is addressed. Salmonella continues to be the top foodborne pathogen associated to poultry in the United States. Salmonella does not originate at the processing plant, but it is a principal control point in the process.
An objective for improved food safety plans is to reduce the number of pathogens that enter the processing plant so that the plant becomes the linchpin of Salmonella control programs. There has been a lot of conversation around applying mitigating controls at the farm and at the hatchery level, with the goal of eliminating pathogens before arriving to the plant.
A one-way solution is not available, but there is sufficient knowledge on which applications are effective in reducing contamination in breeder farms and hatcheries.
Salmonella can be transmitted vertically from breeder hens to progeny and can also be introduced horizontally through various vectors that occur along the production process. In many ways, effective Salmonella control in breeder operations and hatcheries follow a Hazard Analysis and Critical Control (HACCP) approach. Vertical transmission control follows a direct multi-hurdle intervention program, similar to a production line at a processing plant. Critical control checkpoints are established to monitor whether these direct controls are effective or if corrective measures are needed.
In order for these interventions to work, good manufacturing practices (GMP) and sanitation standard operating procedures (SSOP) are needed. GMP’s and SSOP’s isolate the system from outside vectors that introduce contamination from the environment. Therefore, these serve as the foundation for any pathogen control program. Pest control, feed safety programs and traffic control are some examples of a general GMP program.
Vertical transmission can be controlled by a Salmonella vaccination program. Salmonella vaccines are an effective control method but are limited in their broadness. The efficacy of a vaccine is limited by the number of serotypes which can be included in them, so it’s important to prioritize the serotypes on which to focus. Additional environmental controls are needed to prevent new infections at and beyond breeder farms.
A biosecurity program for Salmonella control is not different from what producers apply for any other disease. There is not a single action that will eliminate the introduction of Salmonella into a poultry house, but a comprehensive program does allow for reduction and overall prevention. Effective biosecurity programs against Salmonella include a structural and operational component.
The farm layout and conditions inside and outside of a house or barn serve as physical barriers to Salmonella. Structural maintenance is intended to keep pests and wildlife out, as well as providing human, vehicle and equipment control. The surrounding premises, such as vegetation, ponds and roads, need to be well kept in an effort to deter pests.
Cleaning and disinfection are main operational components. Cleaned and disinfected vehicles and equipment are allowed past the perimeter area of the farm. Develop a plan for sanitizing houses between flocks and establish protocols to maintain a sanitation program during a flock. Enter and exit a house through designated areas and utilize protective clothing and footwear and sanitized equipment after entering a house or barn.
Pest control programs are an additional component of your operational biosecurity program. Flies, in particular, are an important source of Salmonella and their control is crucial. Whenever possible feed, litter, broken eggs and mortality, on which flies lay their eggs, must be removed. Litter on the farm should be managed so that it remains dry. Drinking system management and checking water flow rates help reduce the incidence of wet litter inside a house. Drinking systems must be checked regularly to ensure that there are no leaks. Additional measures include fly traps and using screens and fans to keep flies outside. All integrated pest management programs include an insecticide program that reduce fly numbers and prevent building resistance.
Rodents contribute to the introduction of Salmonella as well as cause damage to the overall structures around the farm. Sanitation and rodent-proofing are both important to prevent an infestation or remove one if an infestation currently exists. Sanitation is simply good housekeeping practices that deny rodents shelter and resources. A clean, well-maintained operation keeps rodents outside, and it will also indicate whether there is some activity inside a house that must be addressed before it becomes a problem. Keep the grass mowed and prevent trash and clutter from collecting around the houses. Maintain a perimeter of the poultry house that is free of brush, trash, weeds and so forth. Finally, install a rodenticide program as a final measure to control population.
Feed and water can also be reservoir of Salmonella. Feed mills need to have GMP programs in place where they achieve Salmonella lethality and prevent the reintroduction after manufacturing and storage. Water sanitation programs prevent the formation of biofilms inside waterlines which could contaminate multiple flocks over time. Water acidification use during a flock, and cleaning waterlines between them, help reduce the accumulation of Salmonella in water lines.
Finally, in order to know that a program is effective, it is essential to collect and analyze data. You can’t control what you can’t measure. It is necessary to determine the type of Salmonella present, how much is present, and where are its reservoirs. This knowledge allows for investments on the critical areas where control is needed.
There are many educational tools available to design a proper Salmonella control program but designing a plan to monitor and make decisions is instrumental to make all of it work.
Rafael Rivera is manager, Food Safety & Production Systems, with the U.S. Poultry & Egg Association based in Tucker, Ga. He can be reached at rrivera@uspoultry.org.
